首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   643篇
  免费   49篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   20篇
妇产科学   10篇
基础医学   71篇
口腔科学   72篇
临床医学   72篇
内科学   123篇
皮肤病学   13篇
神经病学   42篇
特种医学   13篇
外科学   83篇
综合类   10篇
预防医学   55篇
眼科学   27篇
药学   38篇
中国医学   8篇
肿瘤学   36篇
  2023年   10篇
  2022年   19篇
  2021年   24篇
  2020年   23篇
  2019年   35篇
  2018年   36篇
  2017年   27篇
  2016年   34篇
  2015年   31篇
  2014年   27篇
  2013年   39篇
  2012年   66篇
  2011年   61篇
  2010年   32篇
  2009年   26篇
  2008年   32篇
  2007年   30篇
  2006年   26篇
  2005年   14篇
  2004年   8篇
  2003年   18篇
  2002年   7篇
  2001年   5篇
  2000年   8篇
  1999年   6篇
  1998年   2篇
  1997年   3篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1992年   9篇
  1991年   2篇
  1990年   4篇
  1989年   2篇
  1988年   1篇
  1987年   1篇
  1986年   2篇
  1985年   2篇
  1984年   5篇
  1983年   2篇
  1979年   2篇
  1978年   4篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1971年   1篇
  1967年   1篇
  1966年   1篇
排序方式: 共有694条查询结果,搜索用时 15 毫秒
71.
72.
73.
We present a rare case of a symptomatic acquired large coronary fistula and aneurysm secondary to chest trauma that was successfully closed using stent graft. This case is followed by review of the literature.  相似文献   
74.
PURPOSE: A 10-year retrospective study was undertaken of all patients treated for facial gunshot and shrapnel wounds at our medical center to evaluate the outcomes and assess the results of simultaneous management to treat the hard and soft tissue injuries primarily. PATIENTS AND METHODS: A total of 44 patients were treated. Medical documentation of the patients was compiled. All maxillofacial gunshot, shrapnel, and warfare injuries were treated by the oral and maxillofacial surgeon. Other concomitant bodily injuries were treated by pertinent consultant specialists. Patients ranged in age from 8 to 53 years, with a mean age of 24.7 years. Maxillofacial hard and soft tissue injuries were treated definitively in the first operation except when gross contamination, infection, extensive comminution, or general condition precluded this. RESULTS: There were 2 shotgun, 28 bullet, 10 shrapnel, 3 land mine, and 1 breech block injuries. Overall postadmission mortality in this series was 2.2%. Of the 97.7% of the patients who had an injury to the underlying craniofacial skeleton, all required surgical intervention. The soft tissue and underlying bony injuries were addressed concomitantly (in a single stage at the time of primary surgical debridement) in 86.3% of the patients. Nine percent of the patients had a tracheostomy emergently for management of the airway, 6.8% had an intracranial injury, and 2.2% of them required neurosurgery. In the series, 4.5% of the patients had neck wounds that required exploration. Comprehensive treatment was rendered in 1 to 3 major operations (average, 1.5). CONCLUSION: All patients in this series required surgical intervention for treatment of their facial gunshot wounds. Primary treatment of hard and soft tissue injuries of the face at the time of surgical debridement was possible in the majority of our patients. This minimized the number of admissions and did not bear a higher complication rate than other reported series that advocate multiple staged operations to treat such injuries despite the fact that, in our series, flaps were also mobilized for wound closure in the primary phase.  相似文献   
75.
AIM: Dental impressions are potential sources of bacterial contamination which could eventually lead to transmissible infectious diseases through the blood or saliva. Sodium hypochlorite is an effective disinfectant recommended by the American Dental Association (ADA) in a 1:10 dilution for a ten minute immersion to disinfect irreversible hydrocolloid impressions. As the ADA protocol is sometimes neglected in busy practice settings, this pilot study was designed to determine an efficient and effective protocol for disinfection of irreversible hydrocolloid impressions. METHODS AND MATERIALS: Various concentrations of sodium hypochlorite and disinfection times were challenged against irreversible hydrocolloid impressions contaminated with six Gram-positive and Gram-negative bacteria. RESULTS: A two minute immersion time in a 0.6% solution of sodium hypochlorite protocol was found to prevent bacterial growth on the impressions. CONCLUSION: Disinfection of irreversible hydrocolloid impressions in a 0.6% solution of sodium hypochlorite for two minutes was as effective as the ADA's protocol of using a 0.5% sodium hypochlorite solution for ten minutes to destroy the test bacteria.  相似文献   
76.
Serum glutathione peroxidase (GSH-Px) activity and selenium concentration were compared in intrinsic asthmatic patients and non-asthmatic control subjects. Serum GSH-Px activity and selenium concentration were assessed in 46 asthmatic patients and 75 age- and sex-matched non-asthmatic subjects by spectrophotometric assay. Mean serum GSH-Px activity was lower in intrinsic asthmatic subjects (9.4 +/- 2.6 pmol NADPH oxidized/min/g of protein) than in non-asthmatic subjects (16.3 +/- 2.9 pmol NADPH oxidized/min/g of protein). Mean serum selenium was lower in intrinsic asthmatic subjects (1.15 +/- 0.23 microM) than in non-asthmatic subjects (1.98 +/- 0.27 microM). Asthmatic patients have significantly lower concentration of selenium and GSH-Px activity measured in serum.  相似文献   
77.
Kidney transplant recipients are susceptible to various infections due to the use of immunosuppressive drugs. The present study was performed as studies on the prevalence of intestinal fungal and parasitic infections in kidney transplant recipients are limited. A total of 150 kidney transplant recipients and 225 matched immunocompetent outpatients, who were referred to the laboratory of Noor Hospital, Isfahan, were studied. After recording demographic characteristics, direct test and specific laboratory cultures were carried out on the stool specimens. Patients were instructed on sanitary rules and, during each medical visit, they were reminded of the same. The overall prevalence of intestinal parasitic and fungal infections was 33.3% and 58.7%, respectively, in transplant recipients and 20% and 51%, respectively, in the control group; the difference was not statistically significant. The most prevalent intestinal parasite was Entameba coli, which was seen in 9.3% of the study patients and 6.7% of the controls. The most prevalent fungus was Candida sp., which was seen in 22% of the study patients and 24.4% of the control group. Co-existing infection with two or more fungi was seen in 14.8% and 3.4% in the case and control groups, respectively; P <0.001. Interestingly, there was no significant difference in the prevalence of infection by a single organism between the two groups. However, co-existing infection with two or more species was more prevalent in transplant recipients. We conclude that further investigations are needed to evaluate the pathogenesis of infection with these microorganisms.  相似文献   
78.
79.
We have examined the effects of inactivation of the p53 tumor suppressor gene on the incidence of apoptotic cell death in two stages of the adenoma-to-carcinoma progression in the intestine: in early adenomas where p53 mutations are rare and in highly dysplastic adenomas where loss of p53 occurs frequently. Homozygosity for an inactivating germ-line mutation of p53 had no effect on the incidence or the rate of progression of ApcMin/+-induced adenomas in mice and also did not affect the frequency of apoptosis in the cells of these adenomas. To examine the effect of p53 loss on apoptosis in late-stage adenomas, we compared the incidence of apoptotic cell death before and after the appearance of highly dysplastic cells in human colonic adenomas. The appearance of highly dysplastic cells, which usually coincides during colon tumor progression with loss of heterozygosity at the p53 locus, did not correlate with a reduction in the incidence of apoptosis. These studies suggest that p53 is only one of the genes that determine the incidence of apoptotic in colon carcinomas and that wild-type p53 retards the progression of many benign colonic adenoma to malignant carcinomas by mechanism(s) other than the promotion of apoptosis.  相似文献   
80.
ObjectiveMeasurement of anthropometric parameters of long bones can be applied in sex determination and height prediction. The aim of this study was to investigate the value of length of the radius in forensic identification.Materials and methodsCross-sectional analysis of anthropometric parameters of the radius was done by Legal Medicine Organization of Tehran, Iran studying fresh cadavers of Iranian population during 2009 and 2010.ResultsThis study surveyed length of radius of 106 fresh Iranian cadavers, 61 men and 45 women, in the age range of 10–85 years old. The study showed that genders can be distinguished using the length of radius with a sensitivity of 83% and specificity of 96%. Using the regression test, there was significant relation between the height of persons and the length of radius bone. The equations were obtained to estimate the height of the individuals on the basis of radius bone length in different age groups, with an exception in females of 40–64 Years old.ConclusionIn the cases of fresh cadavers, by using the length of radius, we could be able to determine the length of height and gender with high confidence.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号